Automated planter

ABSTRACT

An automated planter includes a locating device arranged to locate a propagation tray; at least one plant extraction device adapted to pull a plant out of a propagation tray located by the locating device; and a delivery assembly arranged to receive a plant extracted by the at least one plant extraction device and deliver the received plant to the ground. The planter lifts the plants out of their cells in the tray by inserting fingers, which are caused to converge to pinch the root ball. A plant transport includes two tracks, such that one can be loaded while the other is transporting plants to the delivery assembly.

FIELD OF THE INVENTION

This invention relates to the field of automated planting, and morespecifically to the planting of plants from a propagation tray.

BACKGROUND OF THE INVENTION

Agricultural farming is a vital component of the food supply system inany country. In the past, such farming was extremely labour intensive.However, over the years technology has been applied to automate varioustasks and thus improve the efficiency of the farming as a whole.

One area where machines have been particularly useful is in repetitivefunctions such as planting. In order for an individual plant (or crop)to enjoy optimum growing conditions, certain conditions must be met; onesuch condition is inter-plant spacing. Machines can be designed toprovide constant spacing.

Although automation of many farming functions has taken place, there arestill aspects where a human interaction is preferable (e.g. where theplant may be damaged). In a semi-automated system, the most likely pointof a ‘bottle neck’ is with the human component.

Other disadvantages of involving humans include labour charges andlimited work hours. With a machine, a minimal human workforce cansuccessfully carry out the same work of much larger all-human workforce.

Certain plants, for example lettuces, leeks, the tobacco plant, and theBrassica plant (examples of which are cabbages and cauliflowers), aregrown in propagation trays until they are a reasonable size. Once theplants are of a suitable size, they can be transferred into a field sothat they grow to maturity. Each propagation tray comprises a grid ofcells, with each cell housing an individual plant.

Traditionally the transfer of such plants to a field has involved themanual removal of each plant from the tray, and then feeding the plantsinto a planting machine. The need for human input means that thisplanting system suffers from the aforementioned problems. There is aneed for a machine that is capable of carrying out the human elements ofthe planting process without damaging the crops being planted.

Ride-on, tractor-drawn planters are known, in which one or more peopleon the trailed unit manually remove plants from the propagation traysand then place the plants into a moving array of cups. The cupstransport the plants to a chute, and they are dropped into the chutewhich then conveys the plants down to the ground. The speed at which thearray of cups is moved thus, in part, determines the eventual spacing ofthe plants in the ground. However, in addition to requiring a largeamount of labour, the use of drop chutes presents a further problem. Thetime taken for a plant to fall through the chutes will depend on anumber of factors, including the weight of the root portion of the plant(which is very dependent on the moisture content) and the quantity andconfiguration of the foliage. These factors can vary from tray to tray,and indeed from cell to sell within a single tray, and so even ifextracted plants are presented at a uniform rate to the top of the dropchute, the rate at which they emerge will vary and so leads to avariation in plant spacing.

Automated planters are known in which rows of plants are pushed out at atime by an array of pusher members (e.g. rods) from “below” thepropagation tray (i.e. from the reverse side, the side opposite to thatof the foliage). The pushed-out plants are conveyed by suitable means todrop chutes, through which they are conveyed to arrive at a plantingshoe. From the shoe the plants are deposited in the ground. Again, theuse of drop chute causes difficulties when trying to achieve even plantspacing. Also, blockages can occur. Subsequent handling of the plants,after they have been pushed out of the tray, poses yet further problems.Additionally, pushing the plants out from the trays can damage theirroots, and variations in root-ball density and consistency can lead todifferent plants being pushed out to different extents. This can furthercomplicate subsequent handling.

There is, therefore, a need for an automated planter that overcomes, atleast partially, one or more of the problems associated with the priorart.

SUMMARY OF THE INVENTION

A first aspect of the present invention provides an automated plantercomprising: locating means arranged to locate a propagation tray; plantextraction means adapted to pull a plant out of a propagation traylocated by the locating means; and delivery means arranged to receive aplant extracted by the plant extraction means and deliver the receivedplant to the ground.

Preferably, the plant extraction means comprises at least one insertionmember for insertion into a root portion of a plant in a located tray,through the upper surface of the root portion, to grip the root portion.

Preferably, the plant extraction means comprises at least two fingersfor insertion into the root portion of a plant in a located tray (i.e.fingers may form the insertion members). It would be appreciated thatthe fingers may take a variety of forms such as pins, blades, prongs ortines.

Preferably, the plant extraction means comprises actuator means operableto cause the fingers to converge.

In certain preferred embodiments the fingers are sprung such that endsof the fingers are biased towards each other.

The fingers may be curved, for example formed from thin metal. In suchcases, the natural resilience of the finger material may bias the freeends of the fingers towards each other, such that some means has to beprovided to force those ends apart.

Preferably, the plant extraction means comprises four fingers, arrangedin two pairs.

In certain preferred embodiments the plant extraction means furthercomprises a spacer member, located between the fingers, and slidable inone direction to push the finger ends apart, and in the oppositedirection to allow the ends to converge.

The spacer member may be a block, with the fingers arranged at sides ofthe block, and the block may have a front edge, between the sides, whichcomprises a cut-out for engaging a stem of a plant.

The plant extraction means may be operable to slide the spacer member tothe ends of the fingers to separate those ends, and further operable tomove the spacer member and fingers to a position relative to thelocating means, such that in use the spacer member and fingers can bepositioned adjacent to an upper surface of a root portion of a plant ina tray, and then to hold the position of the spacer member constantwhilst driving the fingers down past the sides of the space of member,whereby the fingers can be inserted into a root portion of a plant and,at the same time, converge to grip the root portion.

The fingers may be mounted on a support assembly, comprising a supporttube, and the spacer member may be mounted on a control rod, which ismovable inside the support tube to slide the spacer up and down relativeto the fingers. In embodiments comprising a plurality of plantextraction means, the control rods of the spacers may be linked togetherso that the spaces can be slid in unison.

Preferably, the planter further comprises stop means arranged to limitmovement of the spacer member or members towards a located tray so as toprevent or limit compression of a root portion surface by the spacermember. Alternatively, engagement of the spacer member with the surfaceof the root portion itself can be used to limit downward movement of thespacer, enabling the fingers to be driven down, at its sides, so thatthey can enter the root portion, converge and grip the root ball.

Certain preferred embodiments comprise a plurality of plant extractionmeans, arranged in a row, whereby a row of plants can be pulled out of alocated propagation tray simultaneously. The plurality of plantextraction means may be mounted on a gantry, the gantry being movableover a located tray to access a number of the rows. The gantry may bemovable to an extent such that it can reach all of the rows withoutrequiring movement of the propagation tray. Alternatively, if the rangeof movement of the gantry is more limited, the planter may include meansfor moving a partially emptied tray to bring the remaining unemptiedrows into range of the plant extraction means.

In embodiments comprising an array of extraction fingers on a pluralityof plant extraction means, the planter preferably comprises means foractuating the respective fingers of all plant extraction means toconverge substantially simultaneously.

Each plant extraction means may comprise a respective spacer memberslidable inside the respective fingers, the planter comprising means forsliding the spacer members simultaneously.

Advantageously, the planter may further comprise means for adjusting theseparation of the plant extraction means in the row. Thus, the plantermay be adjustable to accommodate different forms of propagation trays.This can avoid the plant grower having to go to the considerable expenseof perhaps purchasing new propagation trays to suit a particularplanter. The planter may incorporate suitable sensors to determine thecell spacing in the propagation trays, and may also comprise actuatormeans for setting the extraction means spacing accordingly.Alternatively, the extraction means spacing may manually adjustablebefore commencing use.

Preferably, the delivery means comprises: a delivery belt assemblyarranged to convey an extracted plant from a first height to a second,lower height, the delivery belt assembly comprising two endless belts ofresilient material, inclined and arranged adjacent one another so as tobe able to grip the foliage part of an extracted plant between opposingsurfaces of the belts; and drive means arranged to drive the belts atthe same speed and such that their opposing surfaces move in the samedirection. Thus, the contra rotating belts are able to gently hold thefoliage part of the plants, the root portions suspended beneath thedelivery belt assembly. By operating the belts at the same speed, thefoliage is not rotated as the plant is conveyed, thereby avoidingdamage.

Preferably, the planter further comprises means for presenting extractedplants to the delivery belt assembly such that the foliage portions ofthe extracted plants are engagable by the endless belts.

In certain embodiments the delivery belt assembly is arranged to dropconveyed plants onto the ground. The planter may further comprise acolter arranged to cut a slot in the ground, the delivery belt assemblybeing arranged to drop plants, root portion first, into the slot. Thus,dropping conveyed plants onto the ground may comprise the step ofdropping the plants onto a surface which is below ordinary ground level.A pair of press wheel may be arranged to close soil around the droppedplants.

Preferably, the delivery means comprises: a delivery assembly operableto receive an extracted plant and convey it from a first height theground; and plant transport means arranged to receive extracted plantsfrom the plant extraction means and present them to the deliveryassembly. The plant transport means may comprise a plurality of holdingports, each port being adapted to receive a root portion of an extractedplant, and control means operable to hold the ports in a static state,whereby the ports can be loaded with extracted plants, and to move theports to convey the received plans to the delivery assembly.

In embodiments comprising n plant extraction means, where n is aninteger, the plant transport means is preferably adapted to provide nholding ports to receive n extracted plants substantiallysimultaneously. Thus, the plant transport means may be adapted toreceive an entire row of plants extracted from the propagation tray.Preferably, the holding ports are provided by an endless belt structure,which may comprise a plurality of fin pairings, wherein each fin pairingcomes together to form a holding port. Preferably, at least one fin ofeach pair comprises a barb for retaining a received root portion in theholding port defined by the pair. The barb is preferably provided at apredetermined height from a base of the holding port, and the height ofeach fin from that base is at least twice the height of the barb. Thisis advantageous as it helps the plant transport means to present thedelivery belt structure with one plant at a time. The tall fins helpkeep the foliage of adjacent plants separated, and so help to avoid theinstances of the foliage of two adjacent plants being “grabbed”simultaneously.

Preferably, the planter further comprises an array of extraction fingersand means for driving the extraction fingers transversely into theholding ports, whereby the extraction fingers can penetrate the sides ofthe root portions of plants placed in the holding ports by the plantextraction means and hold the root portions as the plant extractionmeans is lifted away from the deposited plants. These extraction fingersmay be fins, blades, prongs or tines, or other such suitable structures.They should provide minimal damage to the root structure. With theseextraction fingers pushed in through the sides of the root portions, theplant extraction means can then be lifted away from the deposited plantsin the holding ports. Separation from the plant extraction means is thusassisted by the grip provided by the extraction fingers, and the barbsin the holding ports, where provided.

Preferably, the planter further comprises a second plurality of holdingports, the control means being operable to hold one plurality of holdingports in a static state to enable the plant extraction means to depositextracted plants in the static ports, and at the same time to move theother plurality of holding ports to convey previously deposited plantsto the delivery assembly. The second plurality of holding ports may beprovided by a second endless belt structure.

Preferably, the planter further comprises a sensor arranged to detectfoliage of a plant being conveyed by the plant transport means, thesensor being arranged to provide a signal to a controller, thecontroller being further arranged to control drive means of the planttransport means, whereby if no foliage, or inadequately developedfoliage, is detected the plant transport means can be controlledaccordingly to ensure that adequately developed plants are presented tothe delivery assembly at substantially regular intervals. The sensor maybe arranged to detect the foliage just before the plant is passed to thedelivery belt structure. If inadequate foliage is detected, the endlessbelt of the plant transport means can be “speeded up”, i.e. Indexed twopositions forwards to bring the next viable plant Into position forrelease into the delivery belt system at the appropriate time.

Another aspect of the present invention provides a planter assembly forplanting plants extracted from propagation trays, the planter assemblycomprising a delivery belt assembly arranged to convey an extractedplant from a first height to a second, lower height, the delivery beltassembly comprising two endless belts of resilient material, inclinedand arranged adjacent one another so as to be able to grip the foliagepart of an extracted plant between opposing surfaces of the belts; anddrive means arranged to drive the belts at the same speed and such thattheir opposing surfaces move in the same direction.

Preferably, the plant assembly further comprises means for presentingextracted plants to the delivery belt assembly such that the foliageportions of the extracted plants are engagable by the endless belts.

Advantageously, the planter assembly further comprises plant extractionmeans, arranged to extract a row of plants from a propagation traysubstantially simultaneously, and a plant conveyor, arranged to receivean extracted row of plants from the plant extraction means and topresent the extracted plants sequentially to the delivery belt assembly.

Preferably the planter assembly further comprises a second plantconveyor, and conveyor control means adapted to hold one conveyor in astatic state for receiving extracted plants from the plant extractionmeans, and at the same time to move the other conveyor to conveypreviously received plans to the delivery belt assembly.

Another aspect of the invention provides an automated plantercomprising: plant extraction means adapted to remove a row of plantsfrom a propagation tray; a delivery assembly arranged to receiveextracted plants and deliver those extracted plants to the ground; firstand second plant conveyors, each arranged to receive an extracted row ofplants from the plant extraction means and to present the extractedplants sequentially to the delivery assembly; and plant conveyor controlmeans arranged to control the conveyors such that one is held in astatic state to receive an extracted row of plants from plant extractionmeans while the other is driven to present a previously deposited row ofplants to the delivery assembly.

Yet another aspect of the invention provides method of planting plantsfrom a propagation tray, the method comprising steps of: Inserting atleast one insertion member into the root portion of a plant in thepropagation tray, through the upper surface of the root portion, to gripthe root portion; pulling the plant out of the propagation tray;presenting the extracted plant to delivery means; and using the deliverymeans to convey the extracted plant to the ground.

Preferably, the method further comprises the step of pushing the foliageof the plant to one side before inserting the insertion member.

Advantageously, the step of inserting may comprise driving at least twofingers into the root portion from the foliage side.

Preferably, the method further comprises the steps of pulling the plantout of the propagation tray such that the base of the root portion isseparated from the top of the propagation tray by a distance of no morethan the height of the root portion and then moving the extracted planttransversely to the upper surface of the propagation tray, whereby theplant can be separated from adjacent plants, with which its foliage mayhave been entangled, without pulling those adjacent plants out of thepropagation tray. For example, the plant may be lifted out of thepropagation tray such that the base of its root portion clears the topof the tray by 10-20 mm, and then the plant may be translated sideways.

Preferably, the method further comprises the step of pulling out a rowof plants simultaneously from the propagation tray.

Preferably, the method further comprises the step of approaching the rowof plants from a direction transverse to the row and pushing the foliageof the row of plants to one side before inserting the insertion members.

Advantageously, the method may further comprise the steps of holding theextracted row of plants in alignment and translating the line of plantsin a direction perpendicular to that line; depositing the line of plantsin a conveyor structure having a plurality of holding ports aligned withthe line of plants; and operating the conveyor structure to move thedeposited plants in line to present them in sequence to the deliverymeans.

Another aspect of the invention provides an automated planter assemblycomprising: a planting device; plant extraction means having a pluralityof members, which remove a row of plants from a propagation tray anddeposit them on a plant transport means; propagation tray locatingmeans, which position each propagation tray relative to the plantextraction means; and plant transport means having a static state,wherein the transport means presents a plurality of holding ports toreceive the row of plants, and a moving state, wherein the holding portstransport the plants to the planting device.

It will be understood by the skilled man that propagation trays consistof a plurality of planting cells arranged in a grid formation.

Preferably, the spacing between each plant extraction member is suchthat extraction means correctly aligns with a row on a standardpropagation tray.

Preferably, each plant extraction member may comprise at least twofingers, mounted on a main body, and an actuator means, which causes thefingers to converge, wherein, in use, the fingers engage an individualplant in the propagation tray.

It will be understood that the converging fingers will pinch the soiland root portion of the plant and hold it gently, yet firmly, thuspermitting its removal from the propagation tray.

Advantageously, the actuator may be slidably mounted on the fingers suchthat the movement of the actuator in one direction causes the fingers toconverge, whereas movement in the opposition direction causes thefingers to align substantially parallel to one another.

Preferably, the number of members on the plant extraction means maycorrespond to the number of cells in a row presented by the propagationtrays located in the propagation tray receiving means.

Advantageously, the actuator means may all be controlled by a commoncontrol means so that the row of individual plants may be engagedsimultaneously.

Preferably, the propagation tray locating means comprises a sensor todetermine the number of rows of plants held (i.e. the number of rows inthe propagation tray), wherein this data is fed back to an operatingsystem. Further preferably, the propagation tray may have markingsthereon, which alert the system to its dimensions.

The plant extraction means may move relative to the propagation traylocating means so that once the plants have been removed from a row theextraction means moves on to the next row. Alternatively, thepropagation tray locating means may move the tray so that a full row ofplants is always presented to the extraction means.

The plant transport means may comprise a continuous track of holdingports, which receive the soil and root portion of the plants, and acontrol means, which determines whether the track is moving or static.

Preferably, the continuous track comprises a plurality of fin pairings,wherein each fin pairing comes together to form a holding port.

Advantageously, the plant transport means may comprise two continuoustracks of holding ports, so that when the first track is static thesecond track may be moving. In this way, one track can be filled with arow of plants from the extraction means whilst the second track istransporting a row of plants to the planting device, thus reducing thedown time of the system.

The nature of this assembly is such that a computer system is requiredto coordinate at the associated movements of the planter assembly.

Preferably, the locating means comprises: a housing that holds thepropagation tray(s), which are being worked on by the extraction device;a waiting area where the next propagation tray(s) are stored; and atransport mechanism, which replaces the emptied propagation trays withfresh propagation trays.

Preferably, each extraction member comprises four fingers and anactuating means, located at one end thereof. An end of each extractionmember opposite to the fingers may be connected to a common control bar.

Preferably, the extraction means is arranged to lift each plant out ofits respective cell in a propagation tray.

Preferably, the assembly may further comprise an ejection devicearranged to ensure release of the plants from the extraction means intothe holding ports.

The ejection device may comprise a pin.

Preferably, the planting device comprises a planter delivery belt. Thedelivery belt may comprise two contra rotating belts of soft rubberarranged to travel at the same speed.

Advantageously the assembly may further comprise means for varying therate at which each plant is presented to the delivery belt to determinehow far apart they are planted in the ground.

Another aspect of the invention provides a planter assembly aspreviously described in combination with a propagation tray comprising aplurality of planting cells arranged in a grid formation, the spacingbetween each plant extraction member being arranged such that theextraction means correctly aligns with a row of cells on the tray.

Preferably, the number of members on the plant extraction meanscorresponds to the number of cells in a row of the tray.

In certain preferred embodiments the propagation tray comprises markingsarranged to alert a control system of the assembly to the tray'sdimensions.

Another aspect of the invention provides method of extracting andplanting plants from a propagation tray, the method comprising the stepsof: positioning the propagation tray relative to a plant extractionmeans with propagation tray locating means; removing a row of plantsfrom the tray using the plant extraction means; depositing the row ofextracted plants on a plant transport means, the transport means havinga plurality of holding ports to receive the row of plants; operating theplant transport means to transport the deposited plants to a plantingdevice; and operating the planting device to deliver the plants to theground.

The step of removing the plants may comprise removing the row of plantssubstantially simultaneously from the tray.

Preferably, the step of extracting the plants comprises: inserting arespective at least two fingers into the soil and root portion of eachplant; causing the fingers to converge; and lifting the plant out of itscell.

Preferably, the step of causing the fingers to converge comprisespinching the soil and root portion of the plant.

Preferably, the step of depositing the row of extracted plants comprisesreturning the fingers to a substantially parallel alignment.

Preferably, the transport means comprises at least two tracks, themethod further comprising the steps of depositing an extracted row ofplants in the holding ports of a first, stationary one of said tracks,and simultaneously operating a second one of said tracks, in whichanother row of plants had previously been deposited, to transport saidanother row to the planting device.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which illustrate preferred embodiments of theinvention:

FIG. 1 is a diagrammatic representation of a propagation tray;

FIG. 2 shows the alignment between a propagation tray and the extractionmeans;

FIG. 3 shows the process by which an individual plant is removed from acell of the propagation tray;

FIG. 4 shows the alignment between the extraction means and thetransport means which permits a row of plants to be transferred;

FIG. 5 shows how each individual plant is taken from the end of thetransport means by the planter device;

FIGS. 6 to 9 show, schematically, components of a plant extractionmechanism suitable for use in embodiments of the invention;

FIGS. 10 to 13 are views of components of the plant extraction mechanismfrom FIGS. 6 to 9 in use to extracted a plants from a propagation tray;

FIGS. 14 to 17 are schematic side views of a plant extraction mechanismbeing used to extract a plant from a propagation tray;

FIG. 18 is a schematic representation of an extracted plant beingdeposited in a holding port of a plant conveyor;

FIG. 19 is a schematic plan view of the components of an automatedplanter embodying the invention;

FIG. 20 is a schematic side view of components of an automated planterassembly embodying the Invention;

FIG. 21 is a schematic side view of another automated planter embodyingthe invention;

FIG. 22 is a schematic view of part of the plant extraction means of aplanter embodying the invention; and

FIG. 23 is a schematic view of part of another plant extraction means ofan embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

It is standard practice to grow plants 1 from seed in propagation trays2. Such practice allows the farmer to easily control the plant'senvironment until it has grown to a suitable age. Propagation trays comein a range of sizes, and can have a range of cells 3 therein. The typeof propagation tray used can depend on the type of plant being grown. InFIG. 1, a typical propagation tray 2 is illustrated; the tray ispartially stocked with plants 1, each plant having its own individualcell 3.

Certain embodiments of the invention carry out the task of extractingplants, from such propagation trays, and plant the extracted plants inthe ground.

Extraction of the plants from their propagation trays, and transport ofthe plants to an automated planting device are functions which areautomated in certain embodiments of the invention.

FIGS. 2 & 3 illustrate the components used, in a preferred embodiment,to automate the extraction function.

In FIG. 2, the alignment of the propagation tray 2, and thus the plants1, relative to the extraction means 5 can be appreciated. The alignmentof the tray 2 with the extraction means is controlled by the propagationtray locating means (not shown). In the preferred embodiment, thelocating means comprise: a housing that holds the propagation tray(s),which are being worked on by the extraction device; a waiting area wherethe next propagation tray(s) are stored; and a transport mechanism,which replaces the emptied propagation trays with fresh propagationtrays. A piston arrangement is used in the preferred embodiment, butalternative mechanisms will be appreciated by the skilled man.

In the preferred embodiment, the extraction means 5 has twenty-threeextraction members 6, this number corresponds the number of cell in rowon a standard propagation tray 2. It is appreciated that alternativenumbers of extraction members may also be used effectively.

Each extraction member 6 has four fingers 8 and an actuating means 9,located at one end thereof. The alignment of the tray 2 and theextraction means 5 is such that each extraction member 6 is aligned withan individual cell 3 of the tray 2. At the opposite end of theextraction member 6 to the fingers 8 the member is connected to acontrol bar 7; all of the separate extraction members are connected tothe control bar 7.

The control bar is driven by a single piston 10 and a self-balancingrotor mechanism 11. This arrangement ensures that equal pressure Isenforced by each extraction member 6, thus preventing the system fromlocking up. Each extraction member 6 has a remote control device 12 thatpasses the drive of the piston 10 on to the actuator 9, located on eachextraction member 6.

The interaction between each individual extraction member 6 and anindividual plant 1 can be better appreciated from FIG. 3, which shows athree stage process whereby the plant is removed from its cell in thepropagation tray.

Once the plant is aligned with the extraction member, the member movestowards the plant thus causing the fingers 8 to be inserted into thebase of the plant 4 (comprising soil and roots). The depth the fingers 8pass in the base 4 is determined by the type of propagation tray beingused. Once the fingers 8 have reached the desired depth, the actuator 9is activated by remote control means 12.

The shape of the actuator is such that as it is forced down the fingers8 it causes them to converge. The convergence of the fingers 8 imparts apinching action on the plant base 4 and holds it firmly.

Once the plant is held firmly, the extracting member 6 lifts it out ofits cell 3 in the propagation tray. In order to retain the plant, theactuator 9 is maintained in the active position. To detach the plantfrom the extraction member 6 the actuator returns to its originalposition, thus allowing the fingers 8 to return to their original,substantially parallel, alignment.

It is appreciated that the number of fingers and their spacing may varydepending on the dimensions of the cell size of the propagation traybeing worked. The only limitation on the number of fingers is that theremust be at least two, so as permit the pinching mechanism.

Once the row of plants has been extracted from the propagation tray itmoves on the second function that is automated by certain embodiments ofthe invention, namely the transport and presentation of the individualplants to the planting device. FIGS. 4 & 5 show the components involvedin automating this function in the preferred embodiment.

The alignment of the extraction means 5, laden with a row of extractedplants 1, and the plant transport means 13 can be appreciated from FIG.4.

In the preferred embodiment, the plant transport means 13 comprises twocontinuous tracks 16 on which is mounted a plurality of fins. There aretwo types of fin, and they are arranged alternately around the body ofthe track. Fins 14 & 15 are arranged so that when they come togetherthey form a holding port 17. The holding port 17 is shaped so to receivethe plant base 4 of an individual plant 1. The alignment of theextracting means 5 and the transport means 13 is such that each plant 1locates within a holding port 17. It is appreciated that the number ofholding ports on a track should be at least double the number ofextraction members on the extraction means.

The tracks 16 are arranged side by side and are driven by a common drivemeans. When the system is in operation, only one track is ever moving.In this way, one track can be loaded with plants while the other istransporting its load to the planting device. A clutch arrangement (notshown) allows the movement of the two tracks 16 to be alternatedappropriately.

When transferring the plants from the extraction means to the holdingports of the transport means, the retraction of the actuator should beenough to release the plants. It is appreciated that an additionalejection device may be incorporated to ensure release of the plants intothe holding ports 17. A suitable ejection device may involve a pindriven by the control bar.

Once the row of plants has been deposited on the transport means (sensormeans may be involved to monitor state of plant deposition), the loadedtrack 16 carries the plants to the planting device.

FIG. 5 shows how each individual plant 1 is passed on the automatedplanting device. At the end of the plant transport means is located aplanter delivery belt 18. The delivery belt 18 comprises two contrarotating belts of soft rubber that travel at the same speed. It isimportant that the belts travel at the same speed so that the plants,which are held by their stalks, foliage, leaves or leaf area, are notrotated and damaged as they travel along the belt to the plantingdevice.

The positioning of the delivery belt 18 is such that, as the fins 14 &15 are turning the corner of the track 16 and are moving apart, thestalk, foliage, leaves or leaf area of each plant 1 is presented to thedelivery belt 18. The delivery belt 18 picks up the plants andtransports them to be planted.

The rate at which each plant is presented to the delivery belt candetermine how far apart they are planted in the ground. It isappreciated that other factors can be varied to control the distancingof the plants.

The man skilled in the art will appreciate that it is necessary toinclude sensors through out the system, to ensure that the functions runsmoothly. Suitable sensors include lasers, photo-electric and ultrasonictypes.

In order to coordinate the various components of the system a centralcomputer is used, which collects information from the various sensorslocated around the system.

Referring now to FIG. 6, an extraction mechanism 6 suitable for use inthe plant extraction means of the embodiments of the invention comprisestwo pairs of sprung metal fingers 8. These fingers can also be referredto as prongs. The fingers have been formed in a curved shape, and theresilience of their material means that, although their tips 84 can beurged apart, the tips are biased together. The pairs of fingers areattached to a support block 81 by means of screws 82. The support block81 is in turn connected to and supported on the end of a supportcylinder 83. A control rod 94 extends through a holding the supportblock 81 and through the hollow support cylinder 83 and is attached to aspacer block 90. The spacer block is located between the pairs offingers, and speak curvature of the sprung fingers maintains them incontact with the side surfaces 93 of the block 90. The rod 94 ismovable, up and down relative to the support block 81, and so can beused to slide the block 90 up and down between the sprung fingers. FIG.6 shows the spacer block 90 retracted to a position in which It permitsthe ends 84 of the sprung fingers 8 to converge and almost meet. FIG. 7shows the control rod 94 in an extended position, such that the block 90has been slid to the ends 84 of the fingers, causing those ends or tips84 to be pushed apart. In this configuration, the fingers have slightcurvature, but are substantially parallel.

FIG. 8 is a side view of the extraction mechanism, with the block 90 inthe extended position, as in FIG. 7. The two fingers or prongs 8 of thevisible pair have been laser cut from sheet material. As can be seen,the tips of the teeth 8 do not extend beyond the lower edge of the block90 in this configuration. Thus, the teeth are protected from damage, andthis is the configuration in which the extraction mechanism is to bemoved around the planter apparatus when it is not carrying an extractedplant. It will also be appreciated that, by accommodating the spacer orguide block 90 wholly between the opposed pairs of fingers 8, thefootprint of the extraction mechanism is reduced.

FIG. 9 is a schematic perspective view of the spacer block 90 mounted onthe actuator control rod 94. In this embodiment, the guide block isformed from nylon, but other materials may be used. Also, a front, orleading, face 92 of the block 90 incorporates a cut-out 91 for receivingand locating a stalk of a plant.

FIG. 10 shows a nominal front view of the extraction mechanism fromFIGS. 6 to 9, with the block 90 and control rod 94 in the extendedposition, and positioned with a lower surface of the block 90 in contactwith the outer surface 40 of the root and soil portion 4 of a plant tobe extracted. A stalk 42 of the plants is received in the cut-out 91 inthe front face of the block. This is Illustrated in the partial planview of FIG. 13. The stalk 42 has been pushed slightly forwards, thecut-out 91 permitting the block nevertheless to be accommodated whollywithin the perimeter of the upper soil surface 40. The propagation traydefines a cell 3 which has an upper surface 32, and a lower drainagehole 31. The foliage portion 41 of the plant is indicated generally bythe broken line. In FIG. 11 the support cylinder 83 has been drivendownwards, towards the propagation tray. The block 90 has not beendriven downwards, and is maintained in contact with the upper surface 40of the root portion of the plant. Thus, the fingers 8 that werepreviously spaced apart have been driven down past the sides of theblock 90, through the surface 40 and into the root portion 4 of theplant. At the same time, their sprung nature has caused their tips 84 toconverge, thereby pinching (i.e. gripping) the root ball. With thefingers 8 gripping the root ball 4, the support tube 83 is then pulledupwards to extract the plant from the cell 3, as shown in FIG. 12.

The gripped plant can then be moved to a desired position, for exampleto a stationary indexing belt, and then released in the following way.The support tube 84 can be held at a particular position, and the spacerblock 90 can be driven downwards in relation to the fingers, to drivethe root ball off the fingers. As the block pushes downwards on theroot-ball upper surface, it slides down between the fingers and causesthem to straighten.

Referring now to FIG. 14, this shows a side view of two rows of plantsin a propagation tray. Only the ends of plants of the rows are visible.A plant extraction means comprising a row of plant extraction mechanisms6 is also shown, and again only the end mechanism of the row is visible.Each mechanism comprises an array of fingers 8, insertable into the rootportion of a plant, and an actuator block 90 driveable with respect tothe fingers by means of a control rods 94 to control a pinching actionof the fingers. The fingers are supported on a support block 81 andsupport tube 83. The plant extraction means is operated to move theextraction assemblies 6 in unison in the direction shown by the arrow A.Thus, the extraction assemblies are lowered towards the upper surface 32of the propagation tray and are swept in any direction generallyperpendicular to the row of plants to be engaged and extracted. FIG. 15shows the row of extraction devices 6 in position, over the first row ofplants, just before the pins 8 inserted to grip the plant. In thisembodiment, a stop is provided in the plant extraction means to limitthe downwards movement of the array of spacer blocks 90 so that,although they come close, they do not actually touch the upper surface40 of the plants. Thus, compression of, and damage to the root bail bythe blocks 90 is avoided. As can be seen, the act of bringing the row ofextraction devices 6 into the position shown in FIG. 15 has pushed (i.e.deflected) the foliage 41 of the first row of plants to one side, inparticular towards the adjacent row. Although not visible in the figure,the blocks 90 incorporate cut-outs in their leading faces to receivingand accommodate the stalks 42. The cut-outs and the shape of the blocksare not essential to the fundamental operation of the extraction means,but do provide advantages. FIG. 16 shows the next stage in theextraction method. Here, the support tube 83 has been driven down tourge the pins 8 down past the sides of the stopped block 90 and into theroot portion 4. FIG. 17 shows the final step in the extraction process.The support assembly has been pulled up and away from the propagationtray, lifting the base 44 of the root portion completely out of its cell3, above the upper surface 32. However, before the height of the base 44of the extracted plant above the upper surface 32 of the tray exceedsthe depth of the root portion, the plant extraction means begins tosweep the extracted plants in direction transverse to the tray surface.This enables the foliage 41 to be separated from that of the adjacentrow, with which it may have been entangled, without lifting plants inthe adjacent row out of the tray. Thus, the motion of the extractedplant is shown generally by arrow A. The extraction method and thereforethe summarised as approaching a row of plants from the side, pushing thefoliage over to permit better access to the root portion, inserting oneor more members into the root portion to grip it, pulling the grippedroots out of the propagation tray, and then “tearing” the extracted rowof plants sideways from an adjacent row of plants still housed withinthe tray.

From the position shown in FIG. 17, the row of gripped, extracted plantsis then transported by the plant extraction means and deposited in anarray of holding ports 17, an end view of which is shown in FIG. 18. Anactuator 51 is then used to drive an extraction member 50 (which may bea pin, blade, or other such device) into the root portion 4 from theside (i.e. it is driven generally transversely into the root portion).Then, to release the plants from the extraction means, the position ofthe blocks 90 is held constant whilst the support tube 83 are pulledupwards. This withdraws the pins 8 from the root balls. The array ofextraction mechanisms can then be moved back to extract another row ofplants from the propagation tray. As the extraction assemblies arepulled up and away from the holding ports 17, the Inserted extractionmembers 50 assist proper release, by preventing upwards movement of theplants. When the extraction assemblies have been fully withdrawn awayfrom the holding ports, the actuator 51 then withdraws the extractionpins 50 to permit the held plants to be conveyed in line to a deliverymechanism to deposit them in a prepared ground surface.

Referring now to FIG. 19, another embodiment comprises propagation traylocating means 20 arranged to locate and hold in a predeterminedposition a propagation tray 2. In this simplified example, there are 16cells in 4 rows, three of which have already been emptied. An array offour plant extraction mechanisms the supported on a gantry 60 which ismovable over the tray 2 in a direction shown generally by arrow A. Inthe figure, the array of extraction mechanisms has picked up a row ofplants, whose foliage is shown by broken lines 41. The planter comprisesa first, conveyor 70 and a second conveyor 71, each of which provides aplurality of holding ports 17 for receiving extracted plants from theplant extraction means. The gantry 60 is able to move over bothconveyors to deposit extracted plants in their holding ports. Theconveyors are separated by separating plates 72 which help preventtangling of foliage between plants in the adjacent conveyors. For eachconveyor, an array of extraction blades 50 is provided, supported on acommon drive bar 51. When the extraction means places the row of plantsin the holding ports the drive bar 51 is moved to insert the blades 50into the sides of the root portions to hold them in the holding meanswhile the extraction means is withdrawn, ready to extract another row ofplants. Then, the blades 50 are themselves withdrawn. Movement of thedrive bars 51 is indicated generally by arrows C. Control means, notshown in the figure, is provided, and which is able to hold one of theconveyors in a static state while it operates the other to transportdeposited plants to a delivery mechanism. In the figure, conveyor 70 isshown in its static state, and contains a complete row of depositedplants. Conveyor 71 is being operated by the control means. Its motionis not continuous, but rather comprises a series of Indexed steps topresent the row of deposited plants sequentially, at predeterminedintervals, to the delivery assembly. The delivery assembly comprises twosoft rubber endless belts 18, guided and driven by wheels 70 so as torotate at the same speeds but in opposite directions. The belts arearranged next to each other such that they can take in the foliage of aplant, hold it, and convey it to the ground. The foliage of two plants,held and being conveyed by the drive belts 18, are shown schematicallyin the figure. Rotation of the belts is shown by the arrows D. In thisembodiment the belts 18 are arranged to catch the foliage of plantsconveyed by both conveyors. In other embodiments, the belt arrangementmay be movable between a first position in which it catches plants froma first conveyor and a second position in which it catches plants fromthe second conveyor. The planter also comprises a colter 71 arranged tocut a slot or furrow in the soil. The belts 18 are arranged to releasethe plants they convey into the slot. A pair of press wheels 72 isarranged to trail the colter, to fold in and compact the disturbed soilaround the deposited plants. This arrangement tends to yield arelatively loose central strip of soil in which the plants are planted,with relatively compacted soil on either side. This is advantageous fromthe point of view of water supply to the growing plants. The looser soiltends to sink when watered, yielding a depression in which the root ballsits. This helps to retain water, supplied subsequently, around theroots.

Looking now at FIG. 20, this shows part of a plant conveyor suitable foruse in embodiments of the invention. The conveyor comprises a pluralityof fin pairs 14, 15, which are linked together in chain-like fashion tocreate an endless belt. The pairs of fins come together to defineholding ports 17 for holding plants. As the fins travel around drivewheels 403 the holding ports open to release the previously held plants.Each fin comprises a barb 145 directed inwardly into the holding port 17to assist retention of the received plant until it is due for release.The fins extend to a height which is approximately twice that of thebarb height from the base of the holding ports. These high fin wallshelped to keep the plants separated, and together with the plants helpprevent plants being dragged out prematurely when an adjacent plant isreleased, and whose foliage may have become entangled. The figure shows,in highly schematic form, one plant in the process of being released.Its foliage 41 is about to be captured by a delivery belt assembly 18. Apreviously released plant is being conveyed downwards by the deliverybelts 18, with its foliage and stalk being gripped such that its rootportion 4 is suspended below the delivery belt mechanism. A sensor 400is arranged to detect the foliage of plants in the holding ports justbefore they are due to be released to the delivery mechanism. The sensorsends a signal to a controller 401 which then controls drive means 402coupled to the drive wheels 403 of the conveyor. In the figure, theholding port currently aligned with the sensor 400 contains a plantwhose foliage 410 is inadequately developed. The sensor 400 senses thisand the conveyor, after releasing the preceding plant, quickly indexesforwards two positions so that the delivery belt arrangement 18 receivedproperly developed plants at a relatively uniform rate. As the foliage410 is inadequately developed, it cannot be captured by the deliverybelts 18, and is simply discarded onto the floor as the conveyor isadvanced.

The sensor 400 in FIG. 20 is shown in a position such that it can detectfoliage down within a port defined by the fins. However, it will beappreciated that the sensor may be arranged in other positions. Forexample, the sensor may be arranged slightly above the upper ends of thefins as they travel along, to sense foliage protruding from the holdingports.

A variety of sensors may be used. For example, optical sensors may beused, foliage being detected by sensing the breaking of an optical beam.

The automated planter shown in FIG. 21 comprises a conveyor 70 carryinga plurality of sidewalls 170 on an endless belt, those walls definingholding ports 17 for holding and conveying plants. As the conveyor movesthe plants along their foliage is sequentially presented to a deliverybelt system 18. This belt system comprises two contra-rotating softrubber belts which grip the foliage between them and carry the plantsdownwards and deposit them, root portion first, into a slot 701 cut by acolter 71 with a sharp leading edge 700. Press wheels 72, for firmingthe soil around the deposited plants are arranged to trail the colter.The direction of travel of the device during the planting operation isshown generally by arrow A. The planter also comprises plant conveyorcleaning means 78 which, in this embodiment, is arranged to direct a jetof air at the returning portion of the conveyor belt to clean out theholding ports. In other embodiments, other methods may be used to cleanthe ports. For example, steam and/or brushes may be used.

FIG. 22 shows part of the plant extraction means of another embodiment.The extraction means comprises a plurality of extraction assemblies 6with support tubes 83 connected to a common support bar 84 such thatthey can be driven up and down simultaneously. Control rods 94 extendthrough the common support bar 84 and tubes 83 and carry the spacerblocks 90 used to actuate the pinching operation of the insertionfingers 8. The control rods 94 coupled to a further common support bar96 so that they also can be driven in unison. Downwards motion of theblocks 90 in this embodiment is limited by a stop member 97 arranged tolimit movement of the second support bar 96. It will be appreciated thatin alternative embodiments the stop may be omitted.

FIG. 23 shows part of a further embodiment, where a plurality ofextraction devices on support tubes 83 suspended from a support gantry84, which includes actuation for adjusting the separation S of theextraction mechanisms to suit the particular propagation tray.

It will be appreciated that certain embodiments of the present inventionprovide advantages by employing at least two indexing belts (plantconveyor belts) so that one may be loaded while the other is operated totransport the plants to the delivery mechanism.

The delivery mechanism using contra-rotating soft belts to grip plantfoliage handles the plants in a controlled and delicate way, andprovides a further advantage that undeveloped plants are automaticallyrejected as there is no foliage to grip.

Even if adjacent plants in the propagation trays become entangled,embodiments of the invention can easily separate them by pulling a rowof plants first in one direction, to separate it from an adjacent row,and then by sequentially presenting the plants in the row to a deliverybelt arrangement which pulls each plant from its neighbour in adirection in line with the row.

In certain embodiments, to remove the plants from the propagation traysthe plant extraction means may comprise stainless steel fingers mountedon the end of aluminium tubular bars. The fingers may incorporate amoulded plastic foot 90 that is connected to an extraction pin 94, thatruns through the centre of the aluminium tube. This enables the plantsto be picked out of the propagation trays with the stainless fingers,compressing themselves around the root system of the plant. The fingersmay be held on a carriage frame that is driven on two planes by servomotors. By using these motors great accuracy and speed can be achieved,enabling very high planting speeds. Dispatching the plants off the endsof the fingers is achieved by sliding the plastic foot down the fingersusing the extraction pin. The method of operating these extraction pinsis by a pressure compensating pneumatic cylinder acting on the push offbar. The method of individually selecting plants for planting in thefield is achieved by placing the plants in one of two specially designedbelts. These belts may replicate the propagation tray profile, fromwhich the plants have been removed. By using two identical belts itfacilitates the loading of one belt, whilst at the same time enablingthe second belt to be filled with fresh plants. These index belts areoperated by a drive system that incorporates two clutch/brake units,driven by a common drive motor. By using this system it is possible toindex individual flights of the belt at a rate of five per second andhigher. While the plants are in these belts, a selection is made ofwhich plants are suitable for planting, by examining the foliage of theplant. When the plants reach the end of the index belts, they areremoved by system of two contra rotating belts, covered with materialthat enables the plants to be pinched without damaging them. The beltsare made to contra rotate by a drive unit that incorporates a motor,reversing gearbox, and changeover cylinder. The pneumatic changeovercylinder is used to position the grab position of the delivery belts infront of the respective index belts. Once this pair of delivery beltshas collected the plants they are transported towards the ground, wherethey are ready to be planted in the field. A “V” shaped Coulter is usedto cut a slot in the ground, which is then held open by extended fins.The plants are then despatched off the end of the delivery belts intothis pre-cut slot. As soon as the plants have been placed in this slotthey are immediately pressed into place by two angled press wheels.These wheels also assist in closing the pre-cut slot.

1. An automated planter comprising: a) locating means arranged to locatea propagating tray; b) means adapted to extract a plant out of apropagation tray; c) a delivery assembly arranged to receive extractedplants and to deliver the plants to the ground; d) plant transport meansarranged to receive extracted plants from the extraction means topresent said plants to the delivery assembly; characterised in that theplant transport means comprises a first and a second plant conveyor,each conveyor being adapted to receive extracted plants, and controlmeans operable to hold one conveyor in a static state to receive theplants from said plant extraction means whilst the second conveyor isdriven to present previously deposited plants to the delivery assembly.2. A planter in accordance with claim 1, characterised in that theplanter comprises n plant extraction means where n is an integer, theconveyor being adapted to receive n extracted plants substantiallysimultaneously.
 3. A planter according to claim 1 or claim 2,characterised in that the delivery assembly comprises two endless beltsarranged adjacent one another so as to be able to grip the extractedplants between opposing surfaces of the belts; and drive means arrangedto drive the belts at the same speed and such that their opposingsurfaces move in the same direction.
 4. A planter according to any ofthe preceding claims, characterised in that the transport means areadapted to receive an extracted row of plants from the plant actionmeans and to present the extracted plants sequentially to the deliveryassembly.
 5. An automated planter comprising; a) a delivery assembly forreceiving extracted plan and to deliver said plants to the ground; b) aplant transport means to present plants to the delivery assembly, theplant transport means comprising a plurality of holding ports; c) acontroller for controlling the position of the holding ports relative tothe delivery assembly, d) a sensor. characterised in that the controlleradvances the plant transport means in response to the sensor such thatthe delivery assembly receives plants at a uniform rate.
 6. A planteraccording to any of claims 1 to 4, characterised in that the planttransport means comprises a plurality of holding ports, the plantercomprising a controller for controlling the position of the holdingports relative to the delivery assembly and a sensor, the controlleradvancing the plant transport means in response to the sensor, such thatthe delivery assembly receives extracted plants at a uniform rate.
 7. Aplanter according to claim 5 or 6, characterised in that the sensor isadapted to sense plant foliage and the controller is adapted to indexthe plant transport means so that the delivery assembly receivesproperty developed plants at a uniform rate.
 8. A planter according toany of claims 5 to 7 characterised in that the sensor is arranged todetect foliage of the plant being conveyed by the plant transport means;the sensor being arranged to provide a signal to the controller; thecontroller being further arranged to control drive means of the planttransport means, whereby, if no foliage or inadequately developedfoliage is detected, the plant transport means is controlled accordinglyto ensure that plants are presented to the delivery assembly atsubstantially regular intervals.
 9. An automated planter comprising: a)means adapted to extract a plant out of a propagation tray; and b) adelivery means arranged to receive extracted plants and deliver theplants to the ground; c) the extraction mean comprising means forinserting at least one insertion member into the root portion of a plantto grip the root portion; characterised in that the extraction means areadapted to approach a row of plants from a direction transverse to therow; the extraction means are adapted to push the foliage of the plantsto one side before inserting the inserting member; and the extractionmeans are adapted to pull the plant out of the propagation tray.
 10. Aplanter according to any of claims 1 to 8, characterised in that theextraction means comprises means for inserting at least one insertionmember into the root portion of a plant to grip the root portion, theextraction means are adapted to approach the row of plants from adirection transverse to the row; the extraction means are adapted topush the foliage of the plant to one side before inserting the insertionmember and the extraction means are adapted to pull the plant out of thepropagation tray.
 11. A planter according to claim 9 or 10,characterised in that the extraction means are adapted to separate thebase of the root portion from the top of the propagation tray by adistance of no more than the height of the root portion, the extractionmeans moving the extracted plant transversely to the upper surface ofthe propagation tray.
 12. A planter according to any of claims 9 to 11,characterised in that the extraction means are adapted to pull a row ofplants simultaneously from the propagation tray.
 13. A planter accordingto any of the preceding claims, characterised in that the extractionmeans exact a row of plants in alignment and translates the plants in adirection perpendicular to that line, the extraction means depositingthe line of plants in relation to the plant transport means.
 14. Anautomated planter comprising: a) means adapted to extract the plantsfrom a propagation tray; b) holding ports to locate and hold the plants;characterised in that the planter comprises extraction members adaptedfor insertion into the root portion of the plants, the extractionmembers being driven generally transversely into the root portion of theplants to hold the plants in said holding ports whilst said extractionmeans are withdrawn.
 15. A planter according to any of claims 1 to 13,characterised in that the planter comprises holding ports to locate andhold the extracted plants; the planter comprising extraction membersadapted for insertion into the root portion of the plants, theextraction members being driven generally transversely into the rootportion of the plants to hold the plants in said holding ports whilstthe extraction means are withdrawn.
 16. A plant extraction meanscomprising: a) fingers, the fingers being sprung such that ends of thefingers are biassed towards each other, b) a spacer member locatedbetween the finder, characterised in that c) the extraction meanscomprises means for positioning the spacer member and fingers adjacentto an upper surface of a root portion of a plant and means for holdingthe position of the spacer member constant whilst driving the fingersdown past the sides of the spacer member.
 17. A planter according to anyof claims 1 to 15, characterised in that the plant extraction meanscomprises: a) fingers, the fingers being sprung such that ends of thefingers are biassed towards each other, b) a spacer member locatedbetween the fingers, characterised in that c) the exaction meanscomprises means for positioning the spacer member and fingers adjacentto an upper surface of a root portion of a plant and means for holdingthe position of the spacer member constant whilst driving the fingersdown past the sides of the spacer member.
 18. A plant extraction meanscomprising: a) fingers, the fingers being sprung such that ends of thefingers are biassed towards each other, b) a spacer member locatedbetween the fingers, characterised in that the spacer member is adaptedto engage with an upper surface of a root portion of a plant to allowthe fingers to be driven down past the sides of the spacer member,whereby the fingers are inserted into the root portion and the fingersconverge to grip the root portion.
 19. A planter according to any ofclaims 1 to 15, characterised in that the plant is extraction meanscomprises: a) fingers, the fingers being sprung such that ends of thefingers are biassed towards each other, and b) a spacer member locatedbetween the fingers, the spacer member being adapted to engage with anupper surface of a root portion of a plant to allow the fingers to bedriven down past the sides of the spacer member whereby the fingers areinserted into the root portion and converge to grip the root portion.20. A planter according to claim 17 or 19, characterised in that theplanter comprises stop means for limiting movement of the spacer memberso as to prevent or limit compression of the root portion surface by thespacer member.
 21. A planter according to claim 17, 19, or 20,characterised in that the spacer member comprises a cut out toaccommodate a plant.
 22. A planter according to any of claims 17 or 19to 21, characterised in that the engagement of the spacer member withthe upper surface limits downward movement of the spacer, therebyenabling the fingers to be driven down at its sides, so that they canenter the root portion, converge and grip the root portion.
 23. Aplanter according to any of claims 17 or 19 to 22, characterised in thatthe spacer member is locatable between a retracted position and anextended position in the extended position, the spacer member isconfigured such that the finger tips are prevented from extending beyondthe lower edge of the spacer member.
 24. A planter according to any ofclaims 17 or 19 to 23, characterised in that the planter comprises aplurality of plant extraction means, the planter further comprisingmeans for actuating the respective fingers of the plant extraction meansto converge substantially simultaneously.
 25. A planter according to anyof claims 1 to 15, 17 or 19 to 24, characterised in that the plantercomprises spacing means for setting the exaction means spacing inaccordance with the propagation trays.
 26. A planter according to any ofclaims 1 to 15, 17 or 19 to 25, characterised in that the plantercomprises a plurality of plant extraction means, arranged in a rowwhereby a row of plants can be pulled out of a propagation traysimultaneously.
 27. A planter according to claim 26, characterised inthat the planter comprises means for adjusting the separation of theplant extraction means in a row.
 28. A planter according to any ofclaims 1 to 15 or any of claims 17 or 19 to 27, characterised in thatthe planter is a field planter.
 29. A method of automated plantingcomprising providing: a) locating means arranged to locate a propagatingtray; b) means adapted to extract a plant out of a propagation tray; c)a delivery assembly arranged to receive extracted plants and to deliverthe plants to the ground; d) plant transport means arranged to receiveextracted plants from the extraction means to present said plants to thedelivery assembly. characterised in that the plant transport meanscomprises a first and a second plant conveyor, each conveyor beingadapted to receive extracted plants, and means for controlling theconveyors, the method comprising controlling the plant transport meansto hold one conveyor in a static state to receive the plants from saidplant extraction means whilst the second conveyor is driven to presentpreviously deposited plants to the delivery assembly.
 30. A methodaccording to claim 29, characterised in that the transport means areadapted to receive an extracted row of plants from the plant extractionmeans and the extracted plants are presented sequentially to thedelivery assembly.
 31. A method of automated planting comprisingproviding; a) a delivery assembly for receiving extracted plants and todeliver said plants to the ground; b) a conveyor to present plants tothe delivery assembly, the conveyor comprising a plurality of holdingports; c) a controller for controlling the position of the holding portsrelative to the delivery assembly; d) a sensor characterised in that themethod comprises advancing the conveyor in response to the sensor suchthat the delivery assembly receives plants at a uniform rate.
 32. Amethod according to any of claims 29 or 30, characterised in that theconveyor comprises a plurality of holding ports, the planter comprisinga controller for controlling the position of the holding ports relativeto the delivery assembly and a sensor, the method comprising advancingthe conveyor in response to the sensor, such that the delivery assemblyreceives extracted plants at a uniform rate.
 33. A method according toclaim 31 or 32, characterised in that the sensor is adapted to senseplant foliage and the conveyor is indexed so that the delivery assemblyreceives properly developed plants at a uniform rate.
 34. A method ofautomated planting comprising a) providing means for extracting a plantout of a propagation tray; b) providing means for delivering extractedplants to the ground; the extraction means comprising means forinserting at leas one insertion member into the root portion of a plantto grip the root portion; characterised in that the extraction means:approach a row of plants from a direction transverse to the row; andpull the plant out of the propagation tray.
 35. A method according toclaim 34, characterised in that the extraction means push the foliage ofthe plants to one side before inserting the insertion member.
 36. Amethod according to any of claims 29 to 33, characterised in that theplant extraction means comprising means for inserting at least oneinsertion member into the root portion of a plant to grip the rootportion, characterised in that the extraction means: approach the row ofplants from a direction transverse to the row, and pull the plant out ofthe propagation tray.
 37. A method according to claim 36, characterisedin that the extraction means push the foliage of the plant to one sidebefore inserting the insertion member.
 38. A method according to any ofclaims 34 or 37, characterised in that the base of the root portion isseparated from the top of the propagation tray the extracted plant beingmoved transversely to the upper surface of the propagation tray wherebythe plant is separated from adjacent plants with which its foliage mayhave been entangled, without pulling said adjacent plants out of thepropagation tray.
 39. A method according to any of claims 34 to 38,characterised in that a row of plants is pulled simultaneously from thepropagation tray.
 40. A method according to any of claims 29 to 39,characterised in that a row of plants is extracted in alignment and therow is translated in a direction perpendicular to that line, the line ofplants being deposited in relation to the plant transport means.
 41. Amethod of automated planting comprising. a) providing a plantercomprising means for extracting plants from a propagation tray; b)providing holding ports to locate and hold the plants; characterised inthat the planter comprises extraction members adapted for insertion intothe root portion of the plants, the method comprising driving theextraction members generally transversely into the root portion of theplants to hold the plants in the holding ports whilst said extractionmeans are withdrawn.
 42. A method according to any of claims 29 to 4,characterised in that the method comprises providing holding ports tolocate and hold the plants; the planter comprising traction membersadapted for insertion into the root portion of the plants, the methodcomprising driving the extraction members generally transversely intothe root portion of the plants to hold the plants in the holding portswhilst said erection means are withdrawn.
 43. A method of extractingplants comprising providing: a) fingers, the fingers being sprung suchthat ends of the fingers are biassed towards each other, b) a spacermember located between the fingers, the method comprising engaging thespacer member with an upper surface of a root portion of a plant toallow the fingers to be driven down past the sides of the spacer member,whereby the fingers are inserted into the root portion and the fingersconverge to grip the root portion.
 44. A method according to any ofclaims 29 to 42, characterised in that the method comprises providing:a) fingers, the fingers being sprung such that ends of the fingers arebiassed towards each other, b) a spacer member located between thefingers, the method comprising engaging the spacer member with an uppersurface of a root portion of a plant to allow the fingers to be drivendown past the sides of the spacer member.
 45. A method according toclaim 44, characterised, in that the method comprises providing stopmeans, the stop means limiting movement of the spacer member so as toprevent or limit compression of the root portion surface by the spacermember.
 46. A method according to any of claims 43 or 44 or 43,characterised in that the engagement of the spacer member with the uppersurface limits downward movement of the spacer, thereby enabling thefingers to be driven down at its sides, so that they can enter the rootportion, converge and grip the root ball.
 47. A method according to anyof claims 44 to 46, characterised in that the method comprises providinga plurality of plant extraction means, and actuating the respectivefingers of the plant extraction means to converge substantiallysimultaneously.
 48. A method according to any of claims 29 to 47,characterised in that the method comprises spacing the traction means inaccordance with the propagation trays.
 49. A method according to any ofclaims 29 to 48, characterised in that the planter comprises a pluralityof plant extraction means, arranged in a row whereby a row of plants ispulled out of a propagation tray simultaneously.
 50. A method accordingto claim 49, characterised in that the method comprises adjusting theseparation of the plant extraction means in a row.
 51. A methodaccording to any of claims 29 to 42 or any of claims 42 to 49characterised in that the method is a method of automatic fieldplanting.
 52. An automatic planter according to any of claims 1 to 15 orany of claims 17 or 19 to 27, characterised in that the planter is amobile planter.
 53. A planter as hereinbefore described and as shown inany of the accompanying drawings.